After analysing the brains of people at rest or carrying out complex tasks, researchers at Stanford University have learnt that the integration between those brain regions also fluctuates. When the brain is more integrated, people do better on complex tasks.
‘The brain network fluctuates between periods of higher and lower coordinated blood flow in the different areas of the brain.’
"The brain is stunning in its complexity and I feel like, in a way, we've been able to describe some of its beauty in this story," said study lead author Mac Shine, post-doctoral researcher in the lab of Russell Poldrack, Professor of psychology.
"We've been able to say, Here's this underlying structure that you would never have guessed was there, that might help us explain the mystery of why the brain is organized in the way that it is," Shine added.
For the past 100 years, scientists have understood that different areas of the brain serve unique purposes. Only recently have they realised that the organisation isn't static.
In a three-part project, the researchers used open source data from the Human Connectome Project to examine how separate areas of the brain coordinate their activity over time - both while people are at rest and while they are attempting a challenging mental task.
They then tested a potential neurobiological mechanism to explain these findings.
For the resting state condition, the researchers used a novel analysis technique to examine functional magnetic resonance imaging (fMRI) data of people who weren't doing any particular task.
They found that even without any intentional stimulation, the brain network fluctuates between periods of higher and lower coordinated blood flow in the different areas of the brain. The researchers found that the brains of participants were more integrated while working on complicated task than they were during quiet rest.
"This research shows really clear relationships between how the brain is functioning at a network level and how the person's actually performing on these psychological tasks," noted co-author Poldrack in a paper appeared in the journal Neuron.
The researchers plan to further investigate the connection between neural gain and integration in the brain. They also want to figure out how universal these findings are to other behaviours, such as attention and memory.
This research may also eventually help us better understand cognitive disorders, such as Alzheimer's disease or Parkinson's disease.